Control device

ABSTRACT

A substantially flat control device which a user pushes with two or more fingertips to generate an input, the input being associated with the direction and strength of the combined force applied to the device. The device may be a platform which fingertips rest on and push against, or a platform with a shallow edge which the fingertips grip and push. The device may be positioned on the wrist rest area in front of the keyboard of a laptop computer.

FIELD OF THE INVENTION

[0001] The present invention relates to a control device, and relatesparticularly but not exclusively to a pointing device for a computer orother electronic device. The invention also relates to a laptopcomputer.

BACKGROUND OF THE INVENTION

[0002] Originally trackballs were commonly used in laptop computers, butthey were large, prone to clogging and required frequent cleaning. Hencethey are now rarely seen.

[0003] Laptop computers currently almost all use one of two pointercontrol devices: a “pointing stick”/“nib” (typically a small buttonwhich is pressed with one finger eg as disclosed in EP 685,817A and EP663,648A), or a touchpad. Each device allows the position of theon-screen pointer (typically a small arrow) to be controlled in twodimensions using fingertip movements. The touchpad is becoming morecommon and is generally perceived as easier to use, although both aregenerally considered to be considerably less easy to use than the mousethat is used with desktop computers. However accurate control of thecursor is difficult with both the above devices. Hence, it is quitecommon for users to plug a conventional mouse into a laptop computer,when one is available.

[0004] JP 2000081946 discloses a mouse having, instead of theconventional roller ball, an “operation rod” projecting downwardly fromits lower surface which engages a surface of eg a mouse mat or the likeso that movement of the mouse tilts the rod. The inclination of the rodis detected and the resulting signal is input to a computer through aconventional lead.

[0005] U.S. Pat. No. 5,790,108 discloses a pointing device for acomputer comprising a handle somewhat similar to the shell of aconventional mouse mounted on a gantry for horizontal sliding motion inthe x and y directions. The assembly carries two coils which aremagnetically coupled to fixed magnets and carry feedback currentsderived from a computer whose cursor is controlled by the mouse. Thesecurrents are used to constrain the motion of the device and hence thecursor in various ways, including movement along a straight edge andguiding the cursor to menus and other graphic control elements of thedisplay. In one embodiment the device comprises a stack of the abovecomponents and in another embodiment the device is in the form of ajoystick.

[0006] Neither embodiment could be regarded as a low profile device.

[0007] Many other kinds of equipment use other devices to allow a userto select functions and provide other kinds of control inputs. Forexample, buttons, keys, knobs or rotating wheels may be used.

BRIEF DESCRIPTION OF THE PRESENT INVENTION

[0008] It is an object of the present invention to provide a low profilecontrol device which is suitable for incorporation in a laptop computer.By “low profile” is meant a profile which is sufficiently low to enablethe control device to be accommodated in the thickness of a base portionof a clamshell design laptop computer.

[0009] It is a further object of the present invention to provide a lowprofile control device for a computer (not necessarily a laptopcomputer) which alleviates at least some of the problems encountered inprior art control devices.

[0010] A further object of the invention is to provide a control devicefor a laptop computer which has at least some characteristics of a mouseas used for controlling a desktop computer.

[0011] In one aspect the invention provides a low-profile control devicefor a computer, the control device comprising a fixed mounting and acontrol member connected to the fixed mounting by a connecting means.The control member is acted upon by two or more spaced-apart fingertipsof a user, and travel of the control member is restricted in apredetermined plane. An output means is coupled to said control memberfor generating a vector output signal in response to a force applied bythe user in the predetermined plane.

[0012] In the present specification, the words “fingers” and“fingertips” are used throughout to include thumb and thumbtip, asappropriate. The term “vector output signal” is to be construed toinclude discrete components (eg x and y components) of such a signal.

[0013] Preferably a wrist-rest surface is disposed substantiallyparallel to the plane of travel (normally the horizontal plane) of thecontrol member.

[0014] In one embodiment the control member has an upper surfacesubstantially flush with the wrist-rest surface.

[0015] In another embodiment the control member has an upper surfacerecessed with respect to the wrist-rest surface.

[0016] Preferably the control member is substantially oval in plan view.

[0017] Preferably the travel between extreme positions in said plane isconstrained to be 50 mm or less, more preferably 30 mm or less,desirably 10 mm or less.

[0018] Preferably the device comprises means for restricting travel ofthe control member in said plane to 50 mm or less.

[0019] In one embodiment the control device comprises means forsubstantially preventing movement of the control member in said plane.Accordingly, in this embodiment the control member feels substantiallystationary in use.

[0020] In one embodiment the device is in the form of a platform butwith a shallow edge of 1-5 mm in height all or part of the way around.The fingertips grip the edge and combine to gently push on it in therequired direction. It has been found that the sensitivity of one'sfingertips is such that two or more fingertips can accurately apply adesired force in a desired direction by gripping the shallow edge andthat a surface with a shallow edge can be gripped and used in a waysimilar to the way fingers are used to push a desktop mouse.

[0021] In another embodiment the device is in the form of a flatplatform, on the surface of which the fingertips rest in similarrelative positions as when gripping a conventional computer mouse,gently pushing on the surface in the required direction. It has beenfound that two or more fingertips can apply a desired force in a desireddirection onto a surface at least as well as a single fingertip can.

[0022] In such embodiments the device can be used as an input device forlaptops that feels considerably more similar to a desktop mouse thanconventional solutions (e.g. touchpads or pointing sticks). It exploitsthe fact that a great deal of control and feedback can be experiencedjust by fingertips.

[0023] Preferably the transducer arrangement comprises two transducersarranged to sense orthogonal components of force in said plane and togenerate vector output signal components.

[0024] In another aspect the invention provides a laptop computer havinga wrist-rest surface and a pointing device located in the wrist-restsurface, the pointing device comprising a fixed mounting disposedbeneath the wrist-rest surface and a control member located on the fixedmounting. The control member responds to transverse forces generallyparallel to the wrist-rest surface applied by two or more spaced-apartfingertips of a user, and an output means is coupled to the controlmember for generating a vector output signal in response to thesetransverse forces.

[0025] In one embodiment the control device is responsive to theduration of the force applied to it by the user.

[0026] In another embodiment the control device is arranged to generateindividual outputs responsive to forces applied by different fingertipsof the user during use.

[0027] In another embodiment the control device is arranged in use togenerate a further output signal in response to a torque applied by theuser in said plane.

[0028] In another embodiment the control device is arranged to rotate inresponse to a torque applied by the user in said plane.

[0029] In another embodiment the control device is responsive to a forceorthogonal to said plane applied by fingertips of a user to at least onecontrol surface of the device to generate a corresponding further outputsignal.

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Preferred embodiments of the invention will be described by wayof example only with reference to the accompanying drawings in which:

[0031]FIG. 1 is a plan view of a laptop computer incorporating a controldevice in accordance with the invention;

[0032]FIG. 2 is a partial perspective view taken on FIG. 1 and partiallycut away to show the mounting and transducer arrangement of the device;

[0033]FIG. 3 is a perspective view showing how the control device istypically held with the fingertips;

[0034]FIG. 4 is a perspective view similar to that of FIG. 3 but showinga further embodiment, and

[0035]FIG. 5 is a schematic block diagram showing the cursor controlcircuitry of the laptop of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] Referring to FIG. 1, a laptop computer L of is shown from abovewith the screen 4 opened to reveal the keyboard region 6 and wrist-restarea 5 of the base portion of the laptop. The base portion and lidportion (carrying the screen on its interior) are hinged in conventionalfashion at the base of the screen in a standard clamshell configuration.

[0037] In accordance with the invention the laptop is provided with thecontrol device comprising a shallow control member or platform 1 whichis located in a shallow recess or well 7 in the wrist rest area 5.

[0038] Referring to FIGS. 1 and 2, the platform 1 is fixedly mounted ona post 10 which in turn is mounted for rotation about a vertical axis Ain a support block 11. Support block 11 is connected to conventionalforce sensors 13 and 14 which are in turn fixedly located on supports 15which extend upwardly from the floor of the base portion beneathwrist-rest area 5. Sensors 13 and 14 sense the x and y components offorce applied to the device by the fingertips of a user and transmittedby block 11 and generate corresponding output signals which control themovement of a cursor 9 on the screen 4. The translation of the post 10in the x and y directions is resiliently constrained by these sensors(or other coupling) such that translation of the platform 1 is so smallas to be imperceptible to the user. It is assumed that the force sensors13 and 14 have little or no resistance to shear forces but if necessarythe supports 15 can be made resilient to allow for some shearing stressof sensor 14 when sensor 13 is being compressed and vice versa. Theselection of sensors 13 and 14 is well within the capabilities ofpersons skilled in the art; they can for example be thick film straingauges as disclosed in EP 663,648A whose entire contents areincorporated herein by reference.

[0039] The device can easily be accommodated in a base portion of aconventional clamshell design of case, the base portion having athickness T of eg 10 to 25 mm as shown.

[0040] The platform 1 is generally oval in plan view and hasconventional left and right mouse buttons 2 and 3 near the forwardportion of its periphery. In a variant suitable for use with an AppleMacintosh computer, a single mouse button can be substituted for thesebuttons or the entire platform could be responsive to pressure to outputthe necessary switching signal.

[0041] The platform 1 is free to rotate about axis A as indicated byarrow A1 (FIG. 2), so that left- or right-handers can rotate it to acomfortable angle, then leave it there. FIG. 1 shows it positioned for aright-hander.

[0042] As shown in FIG. 3, a user typically positions his or her indexfinger 16 and second finger 17 over the buttons 2 and 3, as with adesktop mouse, and uses their thumb tip and remaining two fingertips togrip the side 8 of the platform. As the user tries to push the platform,the device registers the overall force applied (i.e. direction andstrength) using conventional sensors as mentioned above. This isconverted to a pointer movement on the screen.

[0043] The height h of sidewall 8 is preferably 1 to 5 mm, and is thesame as or slightly less than the depth of the depression 7. Hence,rather than protruding, the platform 1 is sunk into the depression suchthat its upper control surface is flush with or slightly below the levelof the wristrest area 5.

[0044] As shown in FIG. 3, the sunken area around the platform providesroom for the fingertips (namely the tip of thumb 18 and ring finger 19and little finger 20) to grip it, and the device itself does not impedetyping on the keyboard 6 or closing the laptop lid. Index finger 16 andmiddle finger 17 are spaced apart and rest on buttons 2 and 3respectively.

[0045] In the embodiment of FIG. 4 the depression 7 is dispensed withand the platform 1′ is in the form of a flat plate whose upper controlsurface is flush with the surface of wrist rest area 5 and is providedwith pressure-sensitive switching regions 2′ and 3′ which function asmouse buttons and provide switching outputs for controlling graphicelements (eg selecting menu items) on display 4. Again the platform canbe freely rotated about axis A, and is shown positioned for aright-hander.

[0046] In other embodiments, limited translational movement of theplatform 1 of say + or −10 mm may be allowed, and sensors arranged tomeasure movement, duration of applied force or other quantities may beused in place of or in addition to the force sensors.

[0047]FIG. 5 shows a block diagram showing the connection of the x and yforce transducers 13 and 14 to the circuitry of a computer. In thisdiagram the force transducers produce analog signals for the x and yforce components. These signals are fed via a multiplexer 23 to ananalog-to-digital converter 22, which then sends a digital signal to thecentral processing unit (CPU) 21 of the computer. The CPU has a controloutput connected to a control input of multiplexer 23. The CPU has anoutput via conventional driver circuitry (not shown) to display 4(FIG. 1) which controls the position of the cursor. Switching outputsfrom the buttons 2/2′ and 3/3′ are processed in conventional fashion,not shown.

1-20. Canceled.
 21. A low-profile control device for a computer, thecontrol device comprising: a) a fixed mounting; b) transducer means forgenerating a vector output signal in response to x and y components offorce transmitted thereto; and c) a control member acted upon in the xand y directions by at least two spaced-apart fingertips of a user andmounted for limited travel in the x and y directions on said fixedmounting, said control member being coupled to said transducer means fortransmitting said components of force thereto.
 22. The control deviceaccording to claim 21, wherein said control member has a substantiallyhorizontal fingertip-engaging control surface.
 23. The control deviceaccording to claim 21, wherein said control member has an uprightfingertip-engaging control surface.
 24. The control device according toclaim 23, wherein said control member has a height in the range 1 to 5mm.
 25. The control device according to claim 23, wherein said controlmember is disposed in a well, said well having an upright inner surfaceand said control member having a peripheral outer surface facing saidinner surface and spaced apart therefrom to define a gap between saidinner surface and said peripheral outer surface.
 26. The control deviceaccording to claim 21, further comprising a substantially horizontalwrist-rest surface.
 27. The control device according to claim 26,wherein said control member has an upper surface substantially flushwith said wrist-rest surface.
 28. The control device according to claim26, wherein said control member has an upper surface recessed withrespect to said wrist-rest surface.
 29. The control device according toclaim 21, wherein said control member is substantially oval in planview.
 30. The control device according to claim 21, wherein said controlmember has a horizontal dimension of at least 10 mm.
 31. The controldevice according to claim 30, wherein said dimension is at least 20 mm.32. The control device according to claim 21, comprising means forrestricting travel of said control member in said plane to 50 mm orless.
 33. The control device according to claim 21, comprising means forrestricting travel of said control member in said plane to 30 mm orless.
 34. The control device according to claim 21, comprising means forrestricting travel of said control member in said plane to 10 mm orless.
 35. The control device according to claim 21, comprising means forsubstantially preventing movement of said control member in the x-yplane.
 36. The control device according to claim 21, wherein saidcontrol member is mounted on a pivot mounting for enabling rotation ofsaid control member in the x-y plane by said user.
 37. A keyboardincorporating a control device according to claim
 21. 38. A computerincorporating a control device according to claim 21, the computerhaving a display and cursor control circuitry for displaying a cursor onsaid display, an output of said control device being coupled to saidcursor control circuitry for controlling the movement of said cursor.39. The computer according to claim 38 which is a laptop computer havinga keyboard and a wrist-rest area disposed adjacent to said keyboard andwherein said control device is located in said wrist-rest area.
 40. Alaptop computer having a wrist-rest surface and a pointing devicelocated adjacent to said wrist-rest surface, said pointing devicecomprising: a) a fixed mounting below said wrist-rest surface; b)transducer means for generating a vector output signal in response to xand y components of force transmitted thereto; and c) a control memberacted upon in the x and y directions by a least two spaced-apartfingertips of a user and mounted for limited travel in the x and ydirections on said fixed mounting, said control member being coupled tosaid transducer means for transmitting said x and y components of forcethereto.
 41. The control device according to claim 21, which has atleast one fingertip-operable switch means carried in a peripheral regionof said control member for generating a switching signal distinct fromsaid vector output signal.
 42. The control device according to claim 21,wherein said transducer means includes two transducers for sensingrespective orthogonal x and y force components and generating vectoroutput signal components.
 43. The laptop computer according to claim 40,wherein a recess is formed in said wrist-rest surface and said controlmember is disposed in said recess, said recess having an upright innersurface and said control member having a peripheral outer surface facingsaid inner surface and spaced apart therefrom to define a gap betweensaid inner surface and said peripheral outer surface.
 44. The laptopcomputer according to claim 40, wherein at least one fingertip-operableswitch means is coupled to said control member for generating aswitching signal distinct from said vector output signal.
 45. The laptopcomputer according to claim 40, wherein said control member has a heightin the range of 1 to 5 mm.
 46. A low-profile control device for acomputer, the control device comprising: a) a fixed mounting; b)transducer means for generating a vector output signal in response to xand y components of force transmitted thereto; and c) a control memberacted upon in the x and y directions by at least two spaced apartfingertips of a user and mounted on said fixed mounting for limitedtravel, imperceptible to the user in the x and y directions, saidcontrol member being coupled to said transducer means for transmittingsaid components of force thereto.
 47. The control device according toclaim 46 wherein said control member is substantially oval in plan view.48. The control device according to claim 46 wherein said control memberhas a dimension in the x-y plane of at least 10 mm.
 49. The controldevice according to claim 46, further comprising a wrist-rest surface.50. A method of controlling the position of a cursor on a computerscreen comprising the steps of: a) applying x and y components of forcefrom at least two spaced-apart fingertips of a user to a control memberof a low-profile control device for said computer, said control memberbeing mounted for limited travel in the x and y directions on a fixedmounting; b) transmitting said x and y components of force from saidcontrol member to transducer means coupled to said control member; andc) generating a vector output signal from said transducer means forcontrolling the position of said cursor in response to said x and ycomponents of force.
 51. A method according to claim 50, wherein saidcontrol member is mounted for travel in the x and y directions which isimperceptible to the user.
 52. The method according to claim 50, whereinsaid control member has a shallow edge that can be gripped and used in away similar to the way fingers are used to push a desktop mouse.
 53. Themethod according to claim 50, wherein the fingertips rest on a surfaceof said control member in similar relative positions as when gripping aconventional computer mouse.
 54. The method according to claim 50,wherein the index finger and/or second finger of the user operate one ormore buttons as with a desktop mouse.